An advantage is more surface area of the tire on the pavement, thus more traction, and at the same time you aren't adding additonal weight by adding a wider wheel. I think steering response and cornering ability depends on the height of the sidewall. With a shorter sidewall, I would think there is less "roll" and things are effected less. With a taller sidewall, response and cornering ability would be adversely effected. That's my simple, logical approach to your question, but I am certainly no expert and I could be wrong (it has happened before).